12″ Big Mouth Step Box

CAD

Available to Order

12" wide model.
Smooth or checkerplate lid options.
50% larger opening than traditional step boxes allows you to store more tools, more easily.
Enables the use of unused and hard-to-use frame space.
Adds useful additional storage.
Strong, lightweight aluminum construction.
High-quality automotive bulb seal for water resistance.
Step tread increases safety by reducing the possibility of slipping.

The 12" Big Mouth Step Box is the narrowest in the lineup, built for tight spots where every inch of frame space counts. Whether you're running a day cab, a short wheelbase, or just don’t have room for a bigger box, this compact step box fits where others won’t. Featuring the original Big Mouth design, the lid opening is 50% larger than your average step box. No more awkward half-lids or blocked access. Just smooth, hassle-free access to your tools, straps, or gear when you need them most. Built from ⅛" thick marine-grade aluminum, it’s lightweight but tough and sealed tight with a high-quality rubber bulb seal to keep out water, dirt, and road grime. The built-in step tread gives you extra grip when climbing up, and you can pick between a checkerplate or smooth lid, depending on what matches your rig. It’s easy to install, holds up to rough roads, and makes smart use of space that is otherwise often ignored. Don’t waste perfectly good frame space. Throw on a 12” Big Mouth Step Box and make your truck work a little smarter.

Finish:

Buy from a Dealer

Specs: Part #N/A

- Width

- Height

- Depth

- Weight

50% Larger Opening

Find, store, and access your equipment more quickly and easily with the Big Mouth’s 50% larger door opening.

High-Grip Step Tread

High-grip step tread looks OEM and increases safety by reducing the chance of slipping.

7 Sizes & 2 Finishes

Offered in 7 standard widths and 2 standard finishes, there’s a Big Mouth Step box for every truck.

An Iconic Innovation

Big Mouth Step Box Features

After identifying key design flaws with traditional step boxes, we completely reimagined them. Introducing the original 'Big Mouth' step box. A design you’ll recognize, without the headaches.

Photos & Videos

On the Road

Watch More on Youtube

LEFT UNANSWERED?

FREQUENTLY ASKED QUESTIONS

Find quick answers to the most common questions we receive. If you're still unsure, feel free to reach out to our support team.

Big Mouth Step Boxes are to be mounted with Iconic’s 24” Steel L-Mounting Bracket Set (PN 1900). The brackets include a variety of pre-drilled holes, and the brackets come powder coated in a black finish.

Yes. Iconic offers Big Mouth Step Boxes, both with a smooth or checkerplate lid, in the following widths: 12”, 16”, 18”, 22”, 24”, 30”, and 36”. Custom sizing can be requested but will have a lead time. We stock many different standard sizes.

No. The Big Mouth Step Box is manufactured in such a way that no bracket or shock is required to hold the door open. The door is manufactured to sit open on its own while still being able to clear a deck plate or frame rail.